Process of forming glass tubes for eye-droppers



Nov. 22, 1932. R. H. KOENIG PROCESS OF FORMING GLASS TUBES FOR EYE DROPPERS Filed March 19, 1932 Patented Nov. 22, 1932 v UNITED STATES;

ROBERT- E. KOENIG, o1 HADDON HEIGHTS, NEW JERSEY PBOCESS'OF FORMING crass TUBES FOR EYE-.DROPPEIt-S Application filed March 19, 1932. Serial No. seeped This invention relates to improvements in methods of forming glass tubes for eyedr pp 1 The primary object of the present invention is to provide an improved method for forming the constricted end ofcan'eye-dropper. tube with a beaded tip without the necessity of piercing or otherwise puncturing the glass after the tip has been formed.

Another object of the invention is to provide an improved method. for forming the dropper'tubes with beads about their large ends.

A still further object of the invention is to provide a novel method'of forming two dropper tubes together from a single piece of tubing stock and then separating a constricted central portion of thestock after forming 7 beads about the constricted portion, in such 0 a manner as to leave the constricted portions open and a bead about each which serves as a means of protecting the user of the tube against injury.

The invention Wlll be best understood from a consideration of the following detailed description taken in connection with the accompanying drawing forming part of this specification, with the understanding, however,

that the invention is not confined to any 0 strict conformity with the showing of the drawing but may be changed or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawing Figure l is a View in side elevation of a piece of tubing stock, showing the manner of heating the end edges preparatory to the formation of beads thereon;

Figure 2 is a view of the tubing stock undergoing the second step. in the process and showing the method of heating the central portion to facilitate drawing the same;

Figure 3 illustrates the third step of the method showing the manner of heating the central portion of the drawn part of the tube preparatory to forming the tip beads;

Figure 4 illustrates the fourth step showtip beads to form the individual dropper tubes; Y

Figure 5 illustrates thedropper tubes after the completion Figure 6 is 'a view insideelevation of a complete dropper tube.

of the step illustrated in Fig Referring "now' more particularly to the 7 drawing wherein like'numerals of reference indicate corresponding parts throughout the several views, the numerall indicates asec tion of glasstubing from which a pairof dropper tubes may be formed according to the present method. In carryingout 'the present method the section oftubing liis first heated about its'end edges in anyisuitable manner, as for example, by rotating the tube with each of the edges in aflame 2 and when the end portions or edges of the tube are suffi-cientlysoftened longitudinal pres sure is applied so as to spread the ends ofthe tube and thus form the beads3 shown in Figure 2. The second step in the present method consists in heating an area of the tube at a pointmidway between its ends by means of a plurality of flames 4 and when this'central area has become sufliciently heated the tube is pulled from either end so as to draw out and constri'ct the'central portionin the man ner indicated at 5'. There is thus obtained the elongated body comprisinglthe two'portions 6, each of which has an open end, and the elongated constricted central portion 5 connecting them together. These portions 6 each constitute the barrel ofthe finished dropper tube; 1 V V The next step in the present method is to apply heat through the medium of two flames. each ofwhich is indicated bythe numeral 7, or in any othersuitablemanneig to relatively close areas at the'central partof the con- .stricted portion 5, the body of the tubebeing meanwhile turned so as to form two relatively close rings of heat softened glass.

After these'twocircular areas of softened glass have been formed by the flanges 7, 'presbody to force the same-toward oneanother sure is applied to the ends of the tubu'lar 'ing how the tube is separated between the and this results in the pressing outwardly of 1700 the softened, annular portions of the constricted part 5 to form the annular beads 8.

The two ends of the tubular body 1 are then connected with suitable air tubes and air is forced into the body from each end and during'this period a flame 9 vor any other suitable heating means, is applied to the area of the constricted portion 5 between the beads 8 and the tube'is melted through at this point. Due to the pressure of air within the body of the tube theconstricted' portion between the beads 8 remains open as the glass between V the beads is melted to allow the two sections 6 to be separated and thus there results the two completed dropper tubes 10 each having the constricted tip portion terminating in one of the beads 8 and further having its end open and" not requiring anyfurther treat- -ment before attaching the outer end which carries a head 3 to the usual rubber cap (not shown)," by means of which liquid is drawn into and expelled from the "tube.

' 'From theforegoing it will be readily apparent that by the foregoing method the formation of dropper tubes is greatly eXpedite'dasit is unnecessary after the tube has been completed and the bead formed at the constricted end,.to pierce or openthe constricted' end as is necessary in forming tubes according to the methods at present followed.

'It will, of course, be understood that' the foregoing process may be carried out for the formation of the dropper tubeswithout beads at the constricted ends thereof, if desired. In either case whether the beadsare formed or not the same method of separating the tWo portionsof the tube is followed and in carrying out this method the forcing of air into and through the dropper tubes is continued even after the tubeshave been formed, so that a properly formed aperture at the constrictedendofthe tube will be obtained. If the air injected into the ends of the connected dropper tubes should be cut 0E as soon asthe separation of the tubes is effected there'is a possibility of the ends; completely the restricted part of the body between the said beads while maintaining an air pressure within the bodyto prevent the ends of the restricted portion "adjacent the beads from closing during the melting process.

3. The herein describedmethod of forming a'pair of dropper tubes fromv asingle tubular glass body which: consists in heating the end edges of the body to soften the same, then applyingv longitudinal pressure to the ends of the'body' while in,the softened condition to force the softened portion outw ardly for the formation of a surrounding bead, and then drawing out and constricting the central portion of the body and severing the same at the center ofthe constricted portlon.

4. Theherein de cribed method lof form:

ing'a pair of dropper tubes from a tubular body which consists in reducing the diameter of the body for a predetermined areaimidway between the-ends thereof, then applying a, narrow flame to the central part of the re duced portion, and coincident with the application of-the narrow flame for the pur-- pose of melting 'the center of the; constricted portion, introducing air under pressure into the tubular body and continuing the" discharge of air thereinto afterthe constricted portion has been severed andvuntil 'the tips have'hardened' g i In testimony whereof I hereunto aflix my signature. i

' closing or closing'to such .adegree that the, r

dropper tube will be practically useless,

' Having thus described the invention, what 1. .The herein described method of form- 7 7 ing a pairof dropper tubes from a tubular body which consists in reducing the diameter of the body for a predetermined area midway betweenthe, ends thereof, then softening two'relatively closely related circular areas about the reduced portion,then applying pressure to the two ends of thetubular body to, force outwardly the softened areas 7 to form beads, and finally-separatingthe tubular body between the beaded areas.

, 2. The method of forming a pair of dropper tubesfrom a single tubularglass body which consists .inflfirst heating. the body ,through. a relatively wide areacentrally, I

ROBERT H. KQENIG. 

